bump version to 0.3.0b3
bump version to 0.3.0b3

jeicher/cobrapy,aebrahim/cobrapy,JuBra/cobrapy,zakandrewking/cobrapy,jeicher/cobrapy,jerkos/cobrapy,zakandrewking/cobrapy,JuBra/cobrapy,jerkos/cobrapy,aebrahim/cobrapy